title: Electro-optical modulation at 1550 nm in an as-deposited hydrogenated amorphous silicon p-i-n waveguiding device.
abstract: Hydrogenated amorphous silicon (a-Si:H) has been already considered for the objective of passive optical elements, like waveguides and ring resonators, within photonic integrated circuits at λ = 1.55 μm. However the study of its electro-optical properties is still at an early stage, therefore this semiconductor in practice is not considered for light modulation as yet. We demonstrated, for the first time, effective electro-optical modulation in a reverse biased a-Si:H p-i-n waveguiding structure. In particular, phase modulation was studied in a waveguide integrated Fabry-Perot resonator in which the V(π)⋅L(π) product was determined to be 63 V⋅cm. Characteristic switch-on and switch-off times of 14 ns were measured. The device employed a wider gap amorphous silicon carbide  (a-SiC:H) film for the lower cladding layer instead of silicon oxide. In this way the highest temperature involved in the fabrication process was 170°C, which ensured the desired technological compatibility with CMOS processes.
authors.affiliation: Department of Information Science, Mathematics, Electronics and Transportations (DIMET), Mediterranea University, Via Graziella Loc. Feo di Vito 89122, Reggio Calabria, Italy.
authors.forename: Francesco G
authors.initials: FG
authors.lastname: Della Corte
authors.forename: Sandro
authors.initials: S
authors.lastname: Rao
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Coppola
authors.forename: Caterina
authors.initials: C
authors.lastname: Summonte